sedimentary

Red Sandstone

Arenite (with Iron Oxide cement)

Hardness: 6-7 Mohs (grains), color: brick red to reddish-brown, luster: dull/earthy, grain size: medium (0.06mm to 2mm), specific gravity: 2.2-2.8

Luster: dull/earthy, grain size: medium (0

Identified June 19, 2026More sedimentary →

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Physical properties

Hardness: 6-7 Mohs (grains), color: brick red to reddish-brown, luster: dull/earthy, grain size: medium (0.06mm to 2mm), specific gravity: 2.2-2.8

Formation & geological history

Formed through the accumulation and cementation of sand-sized grains, typically in desert or river delta environments. Its red color indicates formation in an oxygen-rich environment where iron minerals oxidized into hematite.

Uses & applications

Widely used as masonry in architecture, paving stone, decorative landscaping, and occasionally as a source of silica for glassmaking.

Geological facts

The famous red rock formations in Sedona, Arizona, and the Red Rocks Amphitheatre in Colorado are composed of this material. The color acts as a 'fossil' of the ancient climate, representing arid, terrestrial conditions.

Field identification & locations

Identify in the field by its gritty texture (feels like sandpaper) and visible layers or bedding. It is commonly found in the American Southwest and Northern England.